jQuery.extend({
    handleError: function (s, xhr, status, e) {
        // If a local callback was specified, fire it

        if (s.error) {
            s.error.call(s.context || s, xhr, status, e);

        }

        // Fire the global callback

        if (s.global) {
            (s.context ? jQuery(s.context) : jQuery.event).trigger("ajaxError", [xhr, s, e]);

        }

    },
    createUploadIframe: function (id, uri) {


        var frameId = 'jUploadFrame' + id;


        if (window.ActiveXObject) {

            if (jQuery.browser.version == "9.0") {
                io = document.createElement('iframe');
                io.id = frameId;
                io.name = frameId;

            } else if (jQuery.browser.version == "6.0" || jQuery.browser.version == "7.0" || jQuery.browser.version == "8.0") {


                var io = document.createElement('<iframe id="' + frameId + '" name="' + frameId + '" />');

                if (typeof uri == 'boolean') {
                    io.src = 'javascript:false';

                } else if (typeof uri == 'string') {
                    io.src = uri;

                }

            }

        } else {

            var io = document.createElement('iframe');
            io.id = frameId;
            io.name = frameId;

        }
        io.style.position = 'absolute';
        io.style.top = '-1000px';
        io.style.left = '-1000px';

        document.body.appendChild(io);


        return io;

    },
    ajaxUpload: function (s, xml) {
        //if((fromFiles.nodeType&&!((fileList=fromFiles.files)&&fileList[0].name)))


        var uid = new Date().getTime(),
            idIO = 'jUploadFrame' + uid,
            _this = this;

        var jIO = $('<iframe name="' + idIO + '" id="' + idIO + '" style="display:none">').appendTo('body');

        var jForm = $('<form action="' + s.url + '" target="' + idIO + '" method="post" enctype="multipart/form-data" style="display:none"></form>').appendTo('body');

        var oldElement = $('#' + s.fileElementId);

        var newElement = $(oldElement).clone();
        $(oldElement).attr('id', 'jUploadFile' + uid);
        $(oldElement).before(newElement);
        $(oldElement).appendTo(jForm);

        this.remove = function () {

            if (_this !== null) {
                jNewFile.before(jOldFile).remove();
                jIO.remove();
                jForm.remove();
                _this = null;

            }

        }
        this.onLoad = function () {


            var data = $(jIO[0].contentWindow.document.body).text();


            try {


                if (data != undefined) {
                    data = eval('(' + data + ')');

                    try {


                        if (s.success)
                            s.success(data, status);

                        // Fire the global callback

                        if (s.global)
                            jQuery.event.trigger("ajaxSuccess", [xml, s]);

                        if (s.complete)
                            s.complete(data, status);
                        xml = null;

                    } catch (e) {

                        status = "error";
                        jQuery.handleError(s, xml, status, e);

                    }

                    // The request was completed

                    if (s.global)
                        jQuery.event.trigger("ajaxComplete", [xml, s]);
                    // Handle the global AJAX counter

                    if (s.global && !--jQuery.active)
                        jQuery.event.trigger("ajaxStop");

                    // Process result


                }

            } catch (ex) {
                alert(ex.message);

            };

        }
        this.start = function () {
            jForm.submit();
            jIO.load(_this.onLoad);
        };

        return this;


    },
    createUploadForm: function (id, url, fileElementId, data) {
        //create form

        var formId = 'jUploadForm' + id;

        var fileId = 'jUploadFile' + id;

        var form = jQuery('<form  action="' + url + '" method="POST" name="' + formId + '" id="' + formId + '" enctype="multipart/form-data"></form>');

        if (data) {

            for (var i in data) {
                jQuery('<input type="hidden" name="' + i + '" value="' + data[i] + '" />').appendTo(form);

            }

        }


        var oldElement = jQuery('#' + fileElementId);

        var newElement = jQuery(oldElement).clone();
        jQuery(oldElement).attr('id', fileId);
        jQuery(oldElement).before(newElement);
        jQuery(oldElement).appendTo(form);

        //set attributes
        jQuery(form).css('position', 'absolute');
        jQuery(form).css('top', '-1200px');
        jQuery(form).css('left', '-1200px');
        jQuery(form).appendTo('body');

        return form;

    },
    ajaxFileUpload: function (s) {
        // TODO introduce global settings, allowing the client to modify them for all requests, not only timeout
        // Create the request object

        var xml = {};
        s = jQuery.extend({}, jQuery.ajaxSettings, s);

        if (window.ActiveXObject) {

            var upload = new jQuery.ajaxUpload(s, xml);
            upload.start();


        } else {

            var id = new Date().getTime();

            var form = jQuery.createUploadForm(id, s.url, s.fileElementId, (typeof (s.data) == 'undefined' ? false : s.data));

            var io = jQuery.createUploadIframe(id, s.secureuri);

            var frameId = 'jUploadFrame' + id;

            var formId = 'jUploadForm' + id;
            // Watch for a new set of requests

            if (s.global && !jQuery.active++) {
                jQuery.event.trigger("ajaxStart");

            }

            var requestDone = false;


            if (s.global)
                jQuery.event.trigger("ajaxSend", [xml, s]);
            // Wait for a response to come back

            var uploadCallback = function (isTimeout) {

                var io = document.getElementById(frameId);

                try {

                    if (io.contentWindow) {
                        xml.responseText = io.contentWindow.document.body ? io.contentWindow.document.body.innerHTML : null;
                        xml.responseXML = io.contentWindow.document.XMLDocument ? io.contentWindow.document.XMLDocument : io.contentWindow.document;


                    } else if (io.contentDocument) {
                        xml.responseText = io.contentDocument.document.body ? io.contentDocument.document.body.innerHTML : null;
                        xml.responseXML = io.contentDocument.document.XMLDocument ? io.contentDocument.document.XMLDocument : io.contentDocument.document;

                    }

                } catch (e) {
                    jQuery.handleError(s, xml, null, e);

                }

                if (xml || isTimeout == "timeout") {
                    requestDone = true;

                    var status;

                    try {
                        status = isTimeout != "timeout" ? "success" : "error";
                        // Make sure that the request was successful or notmodified

                        if (status != "error") {
                            // process the data (runs the xml through httpData regardless of callback)

                            var data = jQuery.uploadHttpData(xml, s.dataType);
                            // If a local callback was specified, fire it and pass it the data


                            if (s.success)
                                s.success(data, status);

                            // Fire the global callback

                            if (s.global)
                                jQuery.event.trigger("ajaxSuccess", [xml, s]);

                            if (s.complete)
                                s.complete(data, status);


                        } else
                            jQuery.handleError(s, xml, status);

                    } catch (e) {
                        status = "error";
                        jQuery.handleError(s, xml, status, e);

                    }

                    // The request was completed

                    if (s.global)
                        jQuery.event.trigger("ajaxComplete", [xml, s]);
                    // Handle the global AJAX counter

                    if (s.global && !--jQuery.active)
                        jQuery.event.trigger("ajaxStop");

                    // Process result
                    jQuery(io).unbind();

                    setTimeout(function () {

                        try {
                            jQuery(io).remove();
                            jQuery(form).remove();


                        } catch (e) {
                            jQuery.handleError(s, xml, null, e);

                        }

                    }, 100);

                    xml = null;

                }

            };

            if (s.timeout > 0) {
                setTimeout(function () {
                    // Check to see if the request is still happening
                    if (!requestDone) uploadCallback("timeout");

                }, s.timeout);

            }


            try {

                var form = jQuery('#' + formId);
                jQuery(form).attr('action', s.url);
                jQuery(form).attr('method', 'POST');
                jQuery(form).attr('target', frameId);

                if (form.encoding) {
                    jQuery(form).attr('encoding', 'multipart/form-data');

                } else {
                    jQuery(form).attr('enctype', 'multipart/form-data');

                }

                jQuery(form).submit();

            } catch (e) {
                jQuery.handleError(s, xml, null, e);

            }

            jQuery('#' + frameId).load(uploadCallback);

            return {
                abort: function () {}
            };


        }

    },

    uploadHttpData: function (r, type) {

        var data = !type;
        data = type == "xml" || data ? r.responseXML : r.responseText;
        // If the type is "script", eval it in global context

        if (type == "script")
            jQuery.globalEval(data);
        // Get the JavaScript object, if JSON is used.

        if (type == "json") {

            try {
                data = jQuery.parseJSON(data); //第二次修改，ie全兼容

            } catch (e) {
                data = jQuery.parseJSON(jQuery(data).text());

            }

        }
        // evaluate scripts within html

        if (type == "html")
            jQuery("<div>").html(data).evalScripts();


        return data;

    }

});